Wifi problems! Jailbreak or just Ip5 bug?

Hi,

I Jailbreak my iphone 5 like 3 months ago, and i was really happy with it, but this last weeks, my phone is having some connectivity issues. The wifi dont work at all, on any place or Wifi, I have to use my cellular data to use internet or facebook or anything.

I think the most annoying thing is that to use whatsapp, i have to actually enter the app to receive all the messages, if someone send me something it would not send me the notification that i actually receive a message

I compared my iphone 5 with my brother iphone 5, He do not have any connectivity problem, it works just the way it suppouse, the only differences between his phone and mine, its that my iphone is jaibroken... Maybe is this what is causing me this problem?? I have delete almost every tweak and just keep what i actually use, but I will have to restore the phone if is this the reason why i cant use Wifi

Someone have the same issue?, or knows how to fix it??